Electrode holder



R. A. WELCH 2,442,029

ELECTRODE HOLDER May 25, 1948.

Filed April 5, 1944 I N VEN TOR. Fazfiez Wala/z.

Patented May 25, 1943 UNITED srares 'narrar @FFECE 9` Claims.

This invention relates to electrode holders, and particularly to an electrode holder of longitudinally extending form which has all the metal parts thereof completely insulated.

It has been the practice in the art to provide a longitudinally extending electrode holder having a handle and cap portion which are joined to gether by a thread for clamping an electrode in the cap with the end thereof extending at an angle to the longitudinal axis of the holder. The present invention pertains to a holder which has none of its metal parts exposed and which embodies novel clamping means for the electrode and which is so constructed as to rapidly dissipate heat which may be generated in the holder.

Y The holder of the present invention embodies a handle portion which is made of insulating material having a metal insert to reinforce the reduced end portion of the holder. A terminal is supported within the reduced end portion of the handle by a pair of screws which extend through the insert and the thin wall of insulating material at the reduced end portion. The end of the terminal -extends forwardly of the reduced end portion and is provided with an external thread and an axially disposed aperture having a thread of the opposite hand to that of the exterior thread.

An insulating cap of the same outer diameter as the handle contains a metal insert having an internal thread which engages the external thread of the terminal on the end of the handle. The thread of the insert in the cap extends some distance inwardly from the open end so as to have the insulating material of the end extend over the screws projecting through the wall of the reduced portion of the handle which secures the terminal in place. A sloping aperture is provided in the side of the cap and the metal insert near the closed end thereof into which the end of the electrode is inserted. The aperture has angularly disposed walls' which engage the cylindrical electrode along two lines to provide adequate current carrying contact.

A movable jaw has a hat face disposed at the same angle as the aperture and is supported within the insert of the cap. The cap forces the electrode against the angularly disposed wall oi the aperture and provides a third line of engagement therewith. The jaw has a stud provided with a thread which is engageable with the thread in the aperture within the end of the terminal of the handle. The walls of the jaw-receiving aperture of the terminal in the cap are parallel to each other and one Wall is made shorter than the other so that as 'the terminal is screwed into the thread of the insert of the cap, the end of the jaw will Contact the side of greatest length of the jaw-receiving aperture and will be held against rotation so as to have it advance through the aperture thereafter. Due to the disposition oi the longest side relative to the lead oi the thread, the sloping lace ci the jaw will always be parallel to the slope ing aperture through which the electrode is inserted into the cap. As the handle is screwed relative to the cap, the jaw will advance within the cap both by the movement of the cap over the handle and also by the movement produced by the rotation of the handle relative to the stud oi the Jaw.

The metal employed to construct the inserts and jaw is preferably a copper aluminum alloy having a high degree oi conductivity for conducting the current to the electrode and for producing a rapid dissipation of heat which may be generated in the electrode. To assist in the dissipation of this heat, the wall of the handle and cap is deeply corrugated to increase the radiating surface and provide thin wall portions at the base or" the corrugations through which the heat may rapidly pass to the surface or the corrugations.

Accordingly, the main objects oi this invention are: to construct an electrode holder having all of the exterior area entirely insulated; to provide an electrode holder embodying an elongated handle having a reduced end portion for receiving a cap in extension of the handle, the handle and cap being made of insulating material; to conu struct' a holder from an elongated handle and cap which are threaded relative to each other and having a jaw portion supported on a thread oi the opposite hand to that of the thread between the handle and cap for providing movement to the jaw by both` of the threads when the handle and cap are relatively rotated; to provide an electrode holder with a handle and cap made of insulating material which has the outer surface corrugated and having metal inserts and a movable jaw made of a highly conductive metal for rapidly dissipating heat generated in the electrode through the insulating material; and in general to provide an electrode holder which is entirely insulated and which securely supports an angularly disn posed electrode from one end thereof.

Other objects and features oi novelty of this invention will be specifically pointed out or will become apparent when referring, for a better understanding oi the invention, to the following description taken in conjunction with the accornpanying drawing, wherein Figure 1 is a View in elevation of an electrode holder embodying features of this invention;

Fig. 2 is an enlarged sectional View of the structure illustrated in Fig. l, taken on the line 2 2 thereof;

Fig. 3 is a sectional View of the structure illustrated in Fig- 2, taken on the line 3 3 thereof;

Fig. 4 is a sectional view of the structure illustrated in Fig. 2, taken on the line 4 4 thereof;

Fig. 5 is an end view of the structure illustrated in Fig. 4, as viewed from the line 5 5 thereof;

Fig. 6 is a sectional view of the structure illustrated in Fig. 4, taken on the line 6 6 thereof;

Fig, 'l is a View of structure, similar to that illustrated in Fig. 6, showing a different form which the invention may assume, and

Fig. S is a View of structure similar to that illustrated in Fig. 4, showing a modified form thereof.

In Fig. l, an electrode holder I is illustrated which embodies a handle II and a cap I2 which are movable relative to each other. The handle II is made of insulating material and has a hollow interior I3 and a reduced end portion I4 which is reinforced by a hollow cylindrical metal insert I5. A terminal I6 is secured within the insert in the end of the handle by a pair of screws Il. The terminal is provided with an aperture 2G having its axis offset from the axis of the terminal to have a thick wall on one side through which a threaded aperture is provided to receive a set screw 2l. The terminal is secured to the conductors I8 of a cable I9 by the set screw 2|. The cable extends through the handle I I with the cable engaging one side of the interior, as illustrated in Fig. 6, leaving an air space between the opposite side to aid in coolin-g the handle.

The cap I2 is made of insulating material and has a metal insert 22 secured therein by a pair of screws 23. Insulating plugs 24 extend in the openings in the end of the cap for enclosing the heads of the screws 23 for insulating the heads. The terminal I6 has an extending end 25 which is provided with a thread 25 and with an internal aperture 2l having a thread 28. The threads 26 and 28 are of the same pitch and of the opposite hand, for the reason which will be explained hereafter. A jaw 3l of rectangular shape is provided with a stud 32 having a thread 33 thereon which mates with the thread 28 within the aperture 2'I.

A rectangular aperture 34 is provided in the insert 22 for engaging the walls of the jaw 3| to prevent the jaw from turning. It will be noted in Fig, 3, that the wall 36 of the aperture 34 is of shorter length than the wall 3'I opposite thereto providing an extending wall portion 38 on one side of the aperture. This extending wall portion makes certain that the jaw 3l is positioned in a desired manner within the aperture 34 when the cap is screwed upon the handle I I. The insert is provided with an internal thread 39 which mates with the thread 26 on the end of the terminal by which the cap I2 is supported on the handle II. The extending end 4I of the cap projects over the reduced end portion I4 of the handle and over the screws Il extending therethrough so as to completely insulate the screws.

An aperture 42 extends at an angle through the side of the cap I2 and the insert 22 for receiving the end of an electrode 43 which is to be clamped therein. The aperture 42 within the insert is providedwith flat sides 44 and 45 which are disposed at an angle to each other so that each side has line Contact with an electrode 43 clamped against the sides. The face 46 of the jaw 3| is disposed at the same angle as aperture 42 and is made ilat so as to engage the electrode 43 along a line when clamping the electrode in the insert 22. Adequate engagement between the jaw 3I, insert 22, and the electrode 43 is provided -to assure the passage of the current to the electrode without generating heat. The metal of the insert 22, jaw 3I, and terminal I6 is preferably an aluminum copper alloy having high conductivity for conducting the current from the cable I9 to the electrode 43 and for dissipating any heat which may generate within the electrode. The insulating material in the cap I2 and handle II is provided with deep recesses 4l which form corrugations 48 lengthwise 0f the cap and handle for the purpose of increasing the surface area and for reducing the thickness of the wall of the insulating material between the corrugations so as to permit the passage of the heat through the insulating material to the surface of the corrugations.

In Fig. '7, a handle 5I is illustrated having an oval-shaped contour which was found to be of advantage in reducing fatigue in the hand of the operator when the electrode is used over a long period of time.

In Fig. 8, a terminal 52 is illustrated which is made of the aluminum copper alloy and to which a copper sleeve 53 is secured. The terminal 52 may be cast about the copper sleeve or the sleeve may be brazed or otherwise secured to the wall of the aperture of the terminal. The copper sleeve permits the conductors I8 to be securely soldered to the terminal in conductive relation thereto when such a soldered joint is found to be desirable.

When an electrode is to be renewed, the short remaining portion left in the holder will function as a lever for retaining the cap stationary as the handle is rotated relative thereto. This relative rotation withdraws the jaw from engagement with the electrode and permits it to drop from the cap. A new electrode may be inserted in the cap and employed as a lever while grasped by the operator to relatively rotate the cap and handle to advance the jaw and securely clamp the electrode in the holder. Such a replacement operation may be performed by the operator without shifting his hand from the handle, and very little time is consumed when changing electrodes.

The aluminum alloy employed in the metal parts substantially reduces the weight of th'e holder permitting the operator to weld over a long period without undue fatigue.

What is claimed is:

1. In an electrode holder, a handle, a terminal in said handle by which connection is made to a cable extending within said handle having a portion extending from said handle provided with an external thread, said portion having an axially disposed aperture containing a thread of the opposite hand from said external thread, a jaw having a threaded stud which is screwed into the aperture of the terminal, and a cap having a clamping surface, an internal thread for engaging the external thread of the terminal, and an aperture which receives the jaw and prevents it from turning when the handle and cap are relatively rotated for advancing the jaw to clamp an electrode through the action of both of the threads.

2. In an electrode holder, a handle having a reduced end portion, a terminal having an externally threaded end extending from said reduced end portion which is provided with an axially disposed aperture containing an internal thread of the same pitch and the opposite hand from that of the external thread, a jaw having a threaded stud screwed into said aperture, a cap, an insert in said cap having a laterally disposed aperture and a thread engageable with the external thread of said terminal and having a recess for maintaining the jaw against rotation to have the jaw advance to clamp the electrode through the action of both' the external and internal threads when the cap and handle are relatively rotated.

3. In an electrode holder, a handle having a reduced end portion, a terminal having an external threaded end and an axially disposed aperture containing a thread of the same pitch and of the opposite hand to that of the external thread, a jaw having a threaded stud screwed into said aperture, a cap, an insert in said cap, said insert and cap having a laterally disposed aperture, said insert having a thread engageable with the external thread of said terminal and having a recess for maintaining the jaw against rotation when the jaw is advanced to clamp the electrode through the action of both the external and internal threads when the cap and handle are relatively rotated, the walls of the aperture for receiving and retaining said jaW against rotation having one side of greater length than another for guiding and positioning the jaw within the recess when the cap is initially screwed upon the handle.

4. In an electrode holder, a handle made of insulating material, a cap for said handle also made of insulating material, a metal insert in said handle having axially disposed internal and external threads of the opposite hand, a metal insert in said cap having an internal thread engageable with the external thread of said handle insert, said cap insert having a jaw-receiving recess, a jaw having a threaded stud engageable with the internal threads of the handle insert, the cap and insert having a lateral opening for the reception of the electrode which is clamped by the jaw when advanced in said jaw-receiving recess by the threads.

5. In an electrode holder, a handle made of insulating material, a cap for said handle also made of insulating material, a metal insert in said handle having axially disposed internal and external threads of the opposite hand, a metal insert in said cap having an internal thread engageable with the external thread of said handle insert, said cap insert having a jaw-receiving recess, a jaw having a threaded stud engageable with the internal threads of the handle insert, the cap and insert having a lateral opening for the reception of the electrode which is clamped by the jaw when advanced in said jaw-receiving recess by the threads, the jaw-receiving recess being shorter on one side to have the jaw engage the opposite extending side when the cap is applied to the handle for positioning and guiding the jaw into the jaw recess.

6. In an electrode holder, an insulating handle and cap in telescoping extension of each other, a pair of threaded metal inserts in said handle and cap by which they are longitudinally adjusted, and a, jaw threaded in one insert and guided in the other insert for clamping an electrode in the cap insert when the cap and handle are relatively rotated, the thread of the jaw being of the same pitch and the opposite hand from that of the inserts to provide movement to the jaw by the action of both of the threads when the cap and handle are relatively rotated.

7. In an electrode holder, an insulating handle and cap in telescoping extension of each other, a pair of threaded met-al inserts in said handle and cap by which they are longitudinally adjusted, a jaw threaded in one insert and guided in the other insert for clamping an electrode in the cap insert when the cap and handle are relatively rotated, the thread of the jaw being of the same pitch and of the opposite hand from that of the inserts to provide movement to the jaw by the action of both of the threads when the cap and handle are relatively rotated, the guide for the jaw in one of said inserts being longer on one side than on the other for interrupting the rotation of the jaw when the cap is applied to the handle.

8. In an electrode holder, a hollow insulated handle having a reduced end portion, a terminal in said reduced end portion having an externally threaded end extending therefrom, said end containing an axially disposed aperture provided with a thread of'the opposite hand and of the same pitch as that of said external thread, a cap constructed of insulating material, a metal insert in said cap provided with a thread for engaging the external thread of said extending portion of the terminal and having a recess provided with opposite parallel surfaces which are of diiierent length adjacent to said thread, and a jaw having a threaded stud screwed into said aperture and disposed in said recess.

9. In an electrode holder, a longitudinally extending handle rnade of insulating material and having a reduced end portion, a metal insert in the end or the handle extending outwardly from the reduced end portion thereof and provided with an external thread, a cap made of insulating material, an insert in said cap having a thread engageable with the thread of the insert in the handle to have the insulated end portion of the cap extend over the reduced end portion of the handle to insulate all of the metal of the holder on the exterior surface thereof, the insert of the cap being provided with a guide recess for a jaw, a jaw having a threaded stud, said extending end of the handle insert having an axially disposed aperture containing a thread of the opposite hand to the external thread thereof for receiving the stud of said jaw, said cap and insert having a V-shaped aperture extending through the side wall thereof for the reception of an electrode which is clamped in the aperture by the Jaw.

RUSSEL A. WELCH.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 188,968 Shepard Mar, 27, 1877 551,163 Hill Dec. 10, 1895 1,348,530 Willard Aug. 3, 1920 1,908,097 Bende May 9, 1933 2,118,274 Sweda May 24, 1938 2,175,871 Bourne Oct. 10, 1939 2,233,618 Leach Mar. 4, 1941 2,283,162 Bourque May 19, 1942 2,328,067 Forgett Aug. 31, 1943 2,342,966 Paulson Feb. 29, 1944 2,346,368 Donnelly Apr. 11, 1944 2,348,270 Van Dyke May 9, 1944 2,364,507 Bernard Dec. 5, 1944 

